The past several decades have seen a steady increase in the number of unmanned underwater robotic systems deployed for use in the ocean. All of these systems are equipped with energy systems including batteries to accomplish their respective mission.
The primary factors that affect mission duration and sensor payload capability include the overall energy density of a battery module, measured in Watt-hours per kilogram of module mass (Wh/kg); equally important for certain cell chemistries (e.g., Lithium Ion) is circuitry used in the management of the battery components. Underwater robotic systems, especially flooded-hull type systems, require a ruggedized, pressure tolerant energy system capable of operating at all ocean depths.